Sheet delivery system



G. FORRESTER SHEET DELIVERY SYSTEM Sept. 18, 1962 2 Sheets-Sheet 1 FiledDec. 28, 1960 INVENTOR.

1 2%, M 5* gm;

ATTORNEYS Sept. 18, 1962 G. FORRESTER 3,054,613 SHEET DELIVERY SYSTEMFiled Dec. 28, 1960 2 Sheets-Sheet 2 FIG. 5

so 134 28 Fl 6. 6

INVENTOR.

ATTORNEYS Bit gttes 3,54,613 SHEET DEHVERY SYEiTi-IM Gilbert Forrester,Falrnouth, Maine, assignor to S. D. Warren Company, Boston, Mass, acorporation of Massachusetts Filed Dec. 28, 19-50, Ser. No. 78,?24 sCiairns. (c1. 271-49 This invention relates to machinery for handlingsheets of flexible material and more particularly to apparatus forefiecting the delivery of sheets of paper from a sheetconveyor such as aconveyor attached to a sheet cutting machine or to a printing machine.

in papermaking it is frequently desirable to cut the paper which comesfrom the papermaking machines into sheets. This operation may beperformed by high speed cutting machinery which produces a stream of cutsheets traveling at about 150 feet per minute or faster. It isconsequently desirable to employ a layboy to stack and hold these sheetsin order to have a stack of sheets suitable for transfer and packaging.

As the paper is traveling about 2.5 feet per second or faster as itapproaches the layboy it is practically impossible to remove the movingpaper from the machine manually without harming it. This is especiallytrue of papers with special coatings. Even if it were possible to removethe sheets safely, the frequency of delivery is too fast for manualoperation. Thus, an automatic sheet delivery system is required,especially where higher operating speeds are desired.

Conventional delivery systems in general provide a receptacle or layboyfor the sheets as they come oif the end of the cutter. The sheets areejected and are carried by their momentum until they hit a stationarybackstop on the layboy. One disadvantage inherent in such systems isthat the paper sheets must slide in over the prior stacked sheets,thereby increasing the risk of harm to the surfaces of the paper. Thisis particularly true in the case of printing presses where the movingsheets may have undried ink on their surfaces. Another disadvantage isthat the leading edge of a sheet travelling at high speed tends to beunstable due to being projected through the .air, and to fold back uponitself, causing an intolerable condition in the paper pile. Analternative is to slow the moving sheets to a speed at which they may beassisted manually to be laid in a stack, but this necessarily slows thewhole process and is therefore undesirable. One method of slowing thepaper sheets without slowing the cutter is to cause the sheets tooverlap as they leave the cutter, whereby the overall effect is toproduce the same number of sheets moving more slowly at the deliverypoint. This overlapping, however, causes contact between the papersurfaces which may be injurious and is therefore undesirable. In thecase of sheets whose surfaces tend to generate static electric chargeswhen sliding in contact, this may even immobilize them. Another methodof delivery which attempts to avoid contact between paper surfaces andalso to control any unstable condition in the head of the sheet is toemploy a system of grippers or mechanical clamps carried on endlesschains disposed longitudinally over the paper piling position. Theseclamps open to receive the head of the oncoming sheet, close on it andcarry it to its final position, where they open and release the sheet.Such gripper delivery systems are very complex and therefore verycostly. Also they are not readily adjustable for varying sheet lengths,and are therefore feasible for use only in systems where the sheet sizeis never changed. The grippers also tend to mark the sheet where theyhave been attached, causing an undesirable blemish thereon.

Patented Sept. 18, 1962 Accordingly, one object of this invention is toprovide means whereby sheets may be delivered with minimal contacts withtheir surfaces.

Another object of this invention is to deliver the sheets safely at ahigher speed than is now possible without over-lapping the sheets.

A third object of this invention is to provide a system for controllingpositively the forward edge of a sheet moving at high speed without suchsystem being limited to a single sheet dimension, without causing ablemish where the sheet is gripped for such control, and without suchsystem consisting of a complex mechanical system, costly in manufactureand in maintenance. The delivery system hereinafter described is simpleand suited for all sheet dimensions.

A further object of this invention is to provide a novel paper handlingarrangement in which an air stream is used to control the deflection ofa moving paper sheet.

In the described embodiment of the present invention an air pressurehead is employed for deflecting the moving sheets of paper withouttouching them, in combination with a belt delivery system. The beltdelivery system is provided with means for grasping the leading edge ofeach sheet and pulling it along under the belt, which causes the sheetto float into position on a stack of sheets in a controlled fashion, andWithout harmful contact between the surfaces of adjacent sheets andwithout permitting the leading edge to flex backward upon itself. Theair pressure head is arranged to draw the paper toward it rather thandeflect the sheet by blowing against it, thereby providing a degree ofcontrol not heretofore available.

These and other objects and the features of the invention will appear asthe description proceeds with the aid of the accompanying drawings inwhich:

FIG. 1 is a schematic view of the apparatus in side elevation withportions broken away for clarity;

FIG. 2 is a longitudinal vertical cross-section View of an air headconstructed according to the invention;

FIG. 2a is an end elevation view of the air head of FIG. 2;

FIG. 3 is a fragmentary side elevation view of the apparatus showing asheet of paper about to engage the moving belt;

FIG. 4 is a fragmentary side elevation view of the apparatus showing asheet of paper engaging the moving belt;

FIG. 5 is a fragmentary side elevation view of the apparatus showing asheet of paper in contact with the belt;

FIG. 6 is a fragmentary side elevation view of the apparatus showing asheet of paper having been engaged on the belt by the gripping means;and

FIG. 7 is a fragmentary cut-away view in perspective of the belt and anassociated gripping member.

Having further reference to FIG. 1 for a more particular description, asheet of paper 10 is first positioned for delivery by being passedbetween two horizontal holding rollers 12, 14- located on opposite sidesof the sheet of paper 10. The upper roller 14 is journaled for rotationin a pair of brackets 16 which are pivotally supported by a transversepivot rod 18 attached to a suitable standard (not shown). The brackets16 are joined together for rigidity at their mid-sections by atransverse cylindrical member 2%). A transverse support member 22,having a substantially square cross-section, is secured between thebrackets 16' The transverse support member 22 supports a plurality ofblocks. 24- formed to receive the transverse support member 22. Theblocks 24- are generally uniformly spaced across the transversedimension of the sheet 10. A set screw 26 is provided in each block 24-whereby they {a may be securely engaged on the transverse support member22 at appropriate transverse locations.

Each of the blocks 24 is also formed to receive a tubular shaft 28 andhold it perpendicularly to the line defined by the axis of the roller 14and the axis of the pivot member 18. The tubular shaft 23 is held firmlyin place by means of a set screw 30 positioned in the block 24.

The upper end of the tubular shaft 28 is provided with threads 32whereby a connector and an air supply line, not shown, may be attachedthereto. The lower end of the tubular shaft 28 is provided with an airhead assembly indicated generally at 34.

The air head assembly 34 is employed to receive a supply of air underpressure and direct it for the purpose of deflecting the sheet of paper10. The head 34 as shown in FIG. 2 is constructed with a fiat rear plate36 substantially rectangular in shape and formed to receive the tubularshaft 28. Substantially rectangular downwardly extending perpendicularend plates 38, 40 are positioned at the ends of the fiat rear plate 36.In practice, the end plate 38 is positioned nearer the holding rollers12, 14 and transverse to the moving sheet as shown in FIG. 1. A frontface, indicated generally at 42, of the air head assembly 34 next towhich the paper sheet 10 moves, is formed of slightly curved plates 44which are supported in place by the end plates 38, 40 and by side plates46 completing the air head assembly.

The slightly curved front plates 44 are all arc segments of the sameradius and are positioned in relation to each other to overlap slightly.Where the plates 44 overlap small narrow slit openings 48 into theinterior of the air chamber 34 are formed. The openings 48 allow the airunder pressure to escape from the air head 34. The escaping air trav lstangentially to the front plates 44 and forms a high speed film of airon them. Thus, when a sheet of paper 10 is fed in close proximity to thecurved faces 44 of the air assembly 34 as shown in FIG. 1, and the airhead assembly 34 is canted at an angle to the line of travel of thepaper sheet 10, the air film created will cause the paper sheet 10 to bedeflected along the front face 42 of the air head assembly 34. Thisresult is achieved because the front plates 44 in conjunction with theair passages 48 form one side of a venturi passage, the paper sheet 10forming the other side thereof. Since the paper sheet is flexible it isdrawn toward the curved faces 44 because of the well known venturieffect. The net result is to deflect the moving sheet 10 in an aresubstantially that described by the curved front face 42 but separatedtherefrom by the moving film of air.

Vertical adjustment of the assembly 46 will determine the amount whichthe paper 10 can be deflected from its former line of travel. Thus,paper traveling at a high speed may be controlled to change its line oftravel without touching and thereby harming the paper. A plurality ofair heads 34 maybe positioned across the width of the paper sheet 10 asrequired by the sheet width dimension. A deflecting surface 49 may bepositioned as by a bracket 51 at the upper end of the air head assembly34 to deflect the paper 10 downwardly toward the belt system hereinafterdescribed.

The further delivery of the paper sheets 10 is effected by the drivenbelt system shown in side view in FIG. 1. An internally geared neoprenebelt 50 is employed having a smooth outer surface 52. Several belts 50may be used and in practice four are employed. The belts 50 are fittedover a pair of toothed rollers 54, 56 suitable for engaging them. Thetoothed rollers 54, 56 are journaled for rotation in spaced pairs ofsupport standards 58, 60. On its bottom run in which the belt 50 movesaway from the air head assembly 34, the belt 50 declines slightly fromair head assembly 34' and therefore the standard 60 may be positionedlower than the standard 58' or, if the standards 58, 60 and associatedaxes of rollers 54, 56 are in the same horizontal plane, the toothedroller 56 should have a larger radius than the toothed roller 54. Thisarrangement permits the paper 10 to trail without surface contact as itis drawn through the apparatus. The belt 50 travels at 100% of paperspeed which is accomplished by driving one of the toothed rollers 58, 60at the appropriate speed.

Toothed rollers are employed instead of toothed pulleys, which would beacceptable, in order that the belts 50 may be more easily adjusted forvarying widths of paper sheet. Geared belts are used because theyfacilitate transverse synchronization of the gripping membershereinafter to be described, and provide less chance of the belt 50slipping.

In order to grasp the moving sheets of paper 10 there are attached tothe outer surface 52 of the belt 50 a series of substantiallyrectangular gripping members 62. The gripping members 62 are equallyspaced on the belt 50, and are constructed of rigid nylon plates orother similar suitable material. The gripping members 62 are cemented orotherwise attached to the belt 50 as shown in FIG. 7, the cement 64being applied in such manner that the leading end 66 of the grippingmembers 62 is cemented far enough towards the trailing end 68 thereof,to cause the gripping members 62 to be more or less rigidly aflixed tothe belt 50. It will be noted, as seen in FIG. 1, that the grippingmembers 62 are positioned with the trailing end 68 of each grippingmember 62 resting on top of the leading end 66 of the gripping member 62following it on the belt 50. As a result, as th belt 50 passes over thetoothed rollers 54, 56 the associated gripping members 62 assume aposition tangential to the curved portion of the belt 50. This structureproduces an opening of the gripping members 62 as the belt 50 passesover the toothed rollers 54, 56 with the gripping members 62 opening asthe belt 50 begins to arc and closing as it comes off the toothedrollers 54, 56 as shown in FIG. 1.

It will be noted that where a plurality of belts 50 are employed, thegripping members 62 must travel in a synchronized transversely alignedrelationship as between belts 50.

FIGS. 3, 4, 5 and 6 show the operation of the invention. In FIG. 3 asheet of paper 10 is shown in the position it assumes immediately afterits leading edge 70 passes under the air head assembly 34 and has beendeflected thereby. As the leading edge 70 passes beyond the upper end ofthe air head assembly 34, the venturi effect ceases and the leading edge70 is bent downwardly by the deflector 49 toward the toothed roller 54,associated belt 50 and gripping members 62. The belt 50 is driven at100% of paper speed, and in order for the paper 10 to be engaged by thegripping members 62 the paper 10 must approach the belt 50 at the pointwhere the gripping members 62 are traveling around the toothed roller 54and consequently where the horizontal speed of the gripping members 62relative to the paper 10 is less than 100%. In FIG. 3, the paper 10 isshown approaching the belt 50 at a point in its turn at which horizontalspeed of the belt 50 is close to zero.

In FIG. 4 the toothed roller 54 is shown having rotated about 15degrees. At this point, the leading edge 70 of the paper 10 has madecontact with the belt 50 and is advancing on the belt 50 under agripping member 62. The paper 10 thus makes contact with the belt 50 ata point at which the horizontal speed of the belt 50 is about 50% of thepaper speed.

FIG. 5 shows the gripping member 62 beginning to close on the leadingedge 70 of the paper 10', the toothed roller 54 having rotated anadditional 15 degrees, more or less.

When the toothed roller 54 has rotated degrees from its position priorto contact with paper 10, as shown in FIG. 6, the gripping member 62 hasclosed on the lead ing edge 70 of the paper 10 and is moving at of paperspeed carrying the paper 10 with it.

The belt 50 may be of any length necessary to carry a sheet of paper 10to its place of deposit. The trailing edge of the paper will floatslightly lower than the leading edge as it is carried by the belt 50 asindicated by sheet in FIG. 6. The paper 10 is carried by the belt 50 ina line substantially the same as the line at which it approached the airhead assembly 34. Because the trailing edge of the paper 10 is slightlylower than the leading edge thereof, and because the belt 50 declinessomewhat on its bottom run, the gripping members 62 following the oneengaging the paper 14 do not beat against the surface of the paper 10,which beating would occur if the belt 50 were traveling in a horizontalplane. Damage to the paper is thus prevented. It will be noted that theonly surface of the paper 10 which is engaged is that area under thegripping members 62.

There are at least two methods of releasing the paper 10 from thegripping members 62. One method i to allow the paper 10 to drop out ofthe gripping members 62 as they turn upward over the toothed roller 56.As the leading edge 70 of the paper 10 would be given an upward thrustthereby, this method is liable to lead to fouling and subsequent damageto the paper 10. Preferably, however, downwardly extending stop members72 (see FIG. 1) are positioned between the belts 50 at the point atwhich delivery is desired. As the gripping members 62 have only arelatively light grasp on the paper 10, contact of the leading edge 70with the downwardly extending stop members 72 readily releases the sheet10. This disengagement technique deposits the paper sheets 10 into thelayboy without fear of fouling and no harm will result to the leadingedge of most papers by abrupt disengagement at speeds up to 150 feet perminute.

It is my intention to cover all modifications and changes of the exampleof the invention herein chosen for purposes of disclosure which do notconstitute departures from the spirit and scope of the invention.

Having thus described and disclosed a preferred embodiment of myinvention, what I claim as new and desire to secure by Letters Patent ofthe United States is:

1. A flexible sheet material handling system comprising a belt, meansassociated With said belt for engaging a sheet of said flexible materialfor transport by said belt, means for driving said belt, and meansincluding a surface having an air stream flow along said surface, saidlast-mentioned means being positioned to draw said sheet towards saidsurface and to deliver said sheet material to said belt and associatedengaging means.

2. A system for delivery of paper comprising a belt, gripping meansattached to said belt, means for driving said belt and said associatedgripping means, and means for positioning said paper for engagement withsaid gripping means, said last named means including a chamber having aconvex curved surface with ports in the face of said chamber fordischarging air to flow along said surface and means for supplying airunder pressure in said chamber.

3. A system for delivery of moving sheet paper comprising a set ofspaced rollers, a belt mounted on said rollers, means for driving saidrollers and associated belt at the speed of said sheet paper, aplurality of plates attached at the leading edges thereof to said beltto maintain a substantially tangential position to said belt at alltimes, means for positioning said sheet of paper for engagement betweensaid plates and said belt including a chamber having a convex face witha plurality of spaced exit nozzles for exiting compressed airtangentially to said convex face, and means positioning said chamber ina spaced relationship to one of said rollers for delivering said paperto said belt where said belt is moving over said one roller, wherebysaid paper sheet is caused to advance on the said belt between said beltand said tangentially positioned plates.

4. Paper directing apparatus comprising an air chamber, means forsupplying air under pressure to said chamher, and a series of faces onsaid air chamber having openings at their junctures, said openingspositioned to emit a film of high speed air over said faces wherebypaper passed by said faces is directed along the contour thereof.

5. Paper deflecting apparatus comprising a chamber to receive compressedair, one wall of said chamber having a curved outer face with portsdefined in said surface, said ports being arranged in a relationshipsuch that a high speed film of air is created on said surface by saidcompressed air exiting through said ports, and means for passing papersheets close to said surface to be deflected by said film of air towardsaid surface.

6. Apparatus for deflecting a moving sheet of paper comprising an airchamber, overlapping longitudinal curved faces on said air chamberdefining ports in said air chamber between the overlapping portions ofsaid longitudinally curved faces, means for introducing air underpressure into said air chamber, and means for positioning said airchamber in a spaced relation to the line of travel of said paper fordeflecting said paper toward said longitudinally curved faces.

7. A flexible sheet material transport apparatus comprising a set ofspaced horizontal rollers, a belt positioned on said rollers, means forsupporting said rollers to provide a downwardly inclined bottom run fromone of said rollers to the other roller, means for driving said belt, aplurality of spaced transverse rows of thin flexible plates attached tosaid belt, said plates being bonded at the leading edge to said belt tomaintain said plates substantially tangent to said belt, means fordelivering the leading edge of a sheet of paper between said belt and arow of said plates at said one roller to be engaged between said platesand said belt and transported by said lower run of said belt, and meansfor disengaging said paper from between said plates and said belt.

8. A system for delivery of a moving flexible sheet comprising first andsecond spaced horizontal rollers, a belt positioned on said rollers,means for supporting said rollers to provide a downwardly inclinedbottom run from said first roller to said second roller, means fordriving said belt at the speed of said moving sheet, a plurality ofspaced transverse rows of thin flexible plates attached to said belt,said plates being bonded at their leading edge to said belt to maintainsaid plates substantially tangent to said belt, means positioned fordelivering the leading edge of a sheet between said belt and a row ofsaid plates at said one roller to be engaged between said plates andsaid belt and transported by said lower run of said belt, said lastmeans including a chamber having a convex face with a plurality ofspaced exit nozzles for exiting compressed air tangentially to saidconvex face, and means for disengaging said paper from between saidplates and said belt.

Sager Aug. 1, 1933 Matthews Nov. 11, 1941

